If you want to add a little variety to your push ups, consider a Spartan work out. I found this “spartan” exercise routine that you can do pretty much anywhere. It’s 30 reps per exercise and 10 exercises, for a total of 300 reps. It has a good balance between upper and lower body, and provides a break from just push ups. Also, if you’re looking for an aerobic workout, this routine will provide that.